Seroma

A seroma is a pocket of clear serous fluid that sometimes develops in the body after surgery. This fluid is composed of blood plasma that has seeped out of ruptured small blood vessels and inflammatory fluid produced by the injured and dying cells. A seroma is a pocket of clear serous fluid that sometimes develops in the body after surgery. This fluid is composed of blood plasma that has seeped out of ruptured small blood vessels and inflammatory fluid produced by the injured and dying cells. Seromas are different from hematomas, which contain red blood cells, and different from abscesses, which contain pus and result from an infection. Serous fluid is also different from lymph. Early or improper removal of sutures can sometimes lead to formation of seroma or discharge of serous fluid from operative areas. Seromas can also sometimes be caused by injury, such as when the initial swelling from a blow or fall does not fully subside. The remaining serous fluid causes a seroma that the body usually absorbs gradually over time (often taking many days or weeks); however, a knot of calcified tissue sometimes remains. Seromas are particularly common after breast surgery (for example after mastectomy), abdominal surgeries, and reconstructive surgery. They are a treatment target in partial-breast radiation therapy, The larger the surgical intervention, the more likely it is that seromas appear. Larger seromas take longer to resolve than small seromas, and are more likely to undergo secondary infection. Seromas may persist for several months or even years, with the tissue surrounding the seroma hardening over time. On CT scans, seromas have a radiodensity of 0–20 Hounsfield units (HU), generally in the lower part of this range, consistent with clear fluid. Seromas may be difficult to manage at times. Research suggests that the procedure of quilting (inserting interrupted deep stitches in the wound) after mastectomy significantly reduces seroma formation. The removal of seromas by fine-needle aspiration is controversial: it is recommended by some for the reason that seromas can be a culture medium for bacteria, whereas others advise it only for collection of excessive amounts of fluid, because even an aspiration carried out under aseptic conditions carries a certain risk of infection. Depending on the volume and duration of leakage, control of a leak may take up to a few weeks to resolve with aspiration of serums and the application of pressure dressings. Manual lymphatic drainage (MLD) conducted by a trained professional can also assist in managing and treating seromas. If a serum or leak does not resolve (e.g., after a soft tissue biopsy), it may be necessary to take the patient back to the operating room in order to place some form of closed-suction drain into the wound. This usually is not necessary and conservative management prevails. In case of lumpectomy, the formation of a seroma at the lumpectomy site has been cited in medical literature as being beneficial, with claims that it can contribute to preserve the contour of the breast.